Valve



June 25, 1963 o. H. BANKER 3,095,011

Y VALVE Filed sept. e. leso United States Patent O 3,095,011 VALVE 1Oscar H. Banker, Bay Village,` Ohio, assigner to Fawick f .CorporationCleveland, (lhio,` a, corporation of Mich- Igan Filed Sept.. 6, 1960,Ser-.No 54,312

5 Claims.` (Cl. '137-625.69)

force must be overcome before Athe fluideoperated .power steeringmechanism can become elTective. The biasing force exerted by springproduces the initial opposing reaction or feel 4on the steering wheelwhich the driver senses manually as he begins to turnthe steering wheel.

Depending upon the type of vehicle `involved and theA vehiclemanufacturers preference as 'to the Vfeel which ls considered desirable,the spring biasing force'required may vary considerably from one vehicleto another;A If only a single biasing spring were employed,as in Atheplasma substantialre-designof the power steering valve would be requiredto convertf'om one type of ffeel `or neactionefonce `to.anothe-r,-malcing.it impossible to standardize the outside dimensions of`different vehicles;

'Another serious difficulty with such valves having a single biasingspringy was that the valve became completely disabled if the springbroke.

The-present invention is directed to a novel arrangement which avoids,these diculties, .while lat the same timeretaining'all of sheadvantages 'associ-ated withthe basic valveof ymy aforementionedpatents.

4Inaccordance with-the presentinventicn, the previously used vsingleispring :tor biasing the valve to the open center, or neutral, positionis replaced by a plurality of springs whose number may be selectivelyvaried, so as to varythe biasing Vforce, ,without requiringanymodification of the'rest-fof the valve. With this novelarrangementfthelspring bias on the' valve may be readily adjus'tedtosuit-"lichedesignlrequirements of Vanywparticular vehicle; Moreover;even if one'of the springs should break the valve wouldy notbecometotally ,inoperative .as a consequence. The present invention Ahas thefurther advantages of lighter `weight and more compact physical size.V

Accordingly, it is an object of this invention to provide afnovel andimproved `valve for actuating a manually controlled, id operated device.

Another object of this invention is to provide in such a v.valve a novelandimproved Vspring bias arrangement for biasing it Ito its neutralposition.

VAnother object-ofthis invention is to provide a novel.

valve Orthis general type not be'rendered totally" inoperative ifabiasspring should break;

Another object of thisinvention isto provide a novel valve ofthistype'whose springrbias can .be readily changed 4without requinganychangein the outside di'-V mensions of the valveor any other substantialre-design of lthe valve:

Another object of this invention is to provide a novel valve ofthisJ-type which, for a Agiven load capacity, may

be lighter and rnore Ycompact than previous valves for the of suchvalves fora variety 3,095,011 Patented June 25, 1963 Fur-ther objectsand` advantages of 1thisinvention be apparent from 1 thefollowing:detaiIedl description :of a Vpresentlyprehenred embodiment,thereofwhich ill-usf tnated in theraccompanying draait/ing.Y

In the drawing: Y

FIGURE 1 is :a `-lragnlentaryaxialseetionrthrough a valve incorporatingpresent invention;

FIGURE 2 is an exploded perspectivevievv showing fthe.; nove-l spring4biasing arrangement .in thewvalveof FIG". .1;`

and

FIGURE 3 is .a fragmentary `axial sectionshowin-g an t alternativebiasing arrangement in accordance with t the presen-t invention.

Referring first to FIG` 1, the presentinventionsis shown incorporated ina power steering valve ,whichtinciudes a valve body ,10 having, anaxial' borell thereinrand en# larged counterbores 12 and 13' at'theopposite endsofthe bore 11". The valve body defines annular sharpcorners:

14 and. 15 at the `respectivesintersections;.between the counterboresand the bore 11. cornersideine an-- nulas valve-seats, as explainedringreater detailrherein- The -valve body v.is Aformed-with 'any inletpassage-16tl which-communicates with a mund-bottomedgroove 17 extendingcircumferentially around. the valvebore` 11'.- At theinside of=thisgroove-17 there isl an annular groove 18 of rectangular cross sectionwhich opensinto the bore- 11. The vvalve body presen-ts a pair ofaxially spacecLf. annular wa11s'19and- 20 .fat :the op-t radiallyextending,

posite ends of groove 18. These walls define valve seats,t

as explained hereinafter;-

On opposite sides of the is formed .with annular grooves .21.and22.whichf open into the .bore 11 of the power cylinder in the powersteering mechanisme Also, the valve :body is formed with fluid returnpassages `23 and 24,'Lwhich leadl the ccunterbores i12 f and\13,respectively,fto a common passage `25 fwhioh A leads into a `fitting26 connected to the .liuid reservoir (not shown) for the power steeringfluid.

The. valve also includes a spool 30' which'is mounted for relativeIaxial movement/with respect -to Vthe valve -bcdy 10=in eitherdirection. To this -end'- the valve bodyt10 andfvalve sleeve 30linaybeiconnectedin the steering `sys- The spool 30 is disposed inthe groove18 in the valve-body 10;-v From FIG. 1, it will be apparent that theaxial thickness of axial spacingbe` the valve Y body Y the O-ring issubstantially less than `the tween? the end walls` 19-'fand` Y 20vI of tgroove 18.`

At. its right end in FIG. l the valve spool-'is -forined= with anintegral venlarged-end an-ge-34fwhich has asliding t in the-counterbore13 `in. the valve body: Just in-v wardly from this end ,ange 4the spool30 presents a tapered f surface 351for. engagement lagainst the valveseat 15 when the spool 30 is actuated to the leftinFIG. 1.

The spool 301|also carries v ange member -36 which'isslidablyireceivedin `the counterborey 12 in the valve body-.- Thisflange `member presents a tapered surface `3-7 'for engagement with thevalve seat 14 when-thespool 30;'is

moved to` the right in FIG. 1.

A rod'40 issuitably coupled to thespool 30f'and,the flange mernber 36 iscoupledgto the 4spool l30f so lthat: the, rod` 40,-spoo1 30 and lflange,member 36nnove las. a unit.

At its left end inl-TIG. 1 the rodp40is externallyscrewthreaded toreceive `a nut 41. A` pair of thrust plates 42 `groove 18 fthe valvebody A10 and which communicate with outlet pssages (not shown). "leadingto respective"opposite endsr and 43, separated by roller bearings 44,are engaged between nut 41 and an external annular shoulder 4S on valvespool 30. At the right end of the valve spool 30, roller bearings 46 areengaged between the end of the spool extern-al shoulder 48 on the rodl40. With this arrangement when the rod 40 is moved `axially in eitherdirection the valve spool 30 moves in unison with it.

'I'he ilange member 36 on valve spool 30'isengaged between an .annularexternal shoulder 49 on the spool and the right end of a sleeve member50 which is mounted on valve spool 30. With this arrangement the flangemember 36 moves las a unit with valve spool 30\ in either direction ofthe latters movement.

FIG. 1 illustrates the open-center or rneutral position of the valve, inwhich the O-ring 33 is positioned midway between the end walls 19 and 20of the groove 18 inthe valve body, the conical surface 37 on the angemember 36'carried by spool 30 is spaced awlay from engagement with thevalve seat 14, and the conical surface 35 on the end flange 34 of spool30 is similarly spaced away from engagement with the valve seat 15. Atthis time the incoming fluid at 16 is free to ow around the O-ring 33,on either side thereof, into the bore 11 in the valve body and past therespective valve seats 14 and 15 to theV fluid return passages 23 and 24leading to the reservoir, preventing the build up of pressure in eitheroutlet passage 21 or 22.

When the rod 40 is actuated to left in FIG. 1 the O-ring 33 seatsagainst the end wall 19 of valve body groove 18 and the conical surface35 on the spool 30 approaches the valve seat 15. Consequently, uidpressure builds up in the outlet passage 22, while the other outletpassage 21 is blocked from communication with the inlet.

Conversely, when the rod 40 is lactuated to the right in FIG. l, theO-ring iirst seats against the end wall 20 of valve body f groove 18 andthereafter the conical surface 37 on the yflange member 36 carried byspool 30 approaches the valve seat 14. Fluid .pressure now builds up inthe outlet passage 21, while the other outlet passage 2.2 is blockedfrom communication with the inlet passage 16.

'Ilhe valve 4as thus far described operates in laccordance with theprinciples of my earlier U.S. Patents 2,879,748 and 2,914,035,previously mentioned.

In :accordance with the present invention there is provided a novelspring biasing arrangement for biasing the valve spool 30 to its opencenter or neutral position, as shown in FIG. l. Since this springbiasing .arrangement opposes the movement of the valve spool 30 ineither direction away from this open-center position, it will be evidentthat the force exerted by this biasing spring arrangement determines theinitial feel on the steering wheel (i.e., the manual force which must beexerted on the steering wheel when it is rst turned). Also, togetherwith the reaction produced bythe front wheels of the vehicle, it alsodetermines the steering wheel re action during power steering of thevehicle. The present invention 'enables this reaction force or feel tobe selectively varied over a considerable range of values withoutrequiring any change in the valve except the addi` tion or removal ofone or more springs. ,Most important, no change in the outsidedimensions of the valve is required to effect this change.

Referring to FIG. l, the sleeve member 50 is mounted on the outside ofthe valve spool 30 beyond the end flange member 36 thereon. At its leftend in FIG. l the sleeve member 50 is engaged by a nut 51 threadedlymounted on valve spool 30. Nut 51 presents an .axially facing annularshoulder 51a at this end of sleeve member 50. At its opposite end thesleeve member 50 engages the flange member 36. An O-ring 52 is seated inan internal groove 53 formed in this end of the ange member 36.

I A valve housing end cap x4'is detachably mounted on ,and a thrustplate 47 seated against an annular the valve body 10 and together withthe valve body constitutes the valve housing means in the presentinvention. 'Ilhe end cap 54 presents an annular, axially -facinginternal shoulder 55 which is in radial alignment with the shoulder 51aon nut 51. The outside of the sleeve member 50 land the inside of theend cap 54 together define an annular space 56 which extends from thesealigned shoulders 51a and 55 axially to the right in FIG. l up to the`outer end faces of the valve body 10 and the flange member 36 on thevalve spool 30. The novel biasing :arrangement of the present inventionis mounted -in this annular space.

In the embodiment shown in FIGS. 1 and 2 the novel spring biasingarrangement of the present invention comprises a pair of confrontingannui-ar members 57 and 58, which preferably are of nylon, Teflon,polyethylene or other suitable plastic material. Members 57 and 58together constitute the spring retainer means in the present invention.They are slidably received within the annular vspace 56 and have asubstantial radial clearance from the annular inside wall 56a of the endcap 54 which extends around this space. These annular members are formedwith central axial bores 5-9 and 60, respectively, for slidableengagement with the outside of the sleeve member 50.

As shown in FIG. 2, the annular member 57 is formed with .a plurality ofinwardly facing cylindrical recesses 61 arranged in a circular seriesaround the axis of the bore 59. Each of these recesses 61 is open at theaxially inward end of the member 57 and is closed at the latters axiallyoutward end.

The other annular member 58 is similarly formed with an identical groupof open-ended recesses 62, each of which is open at the axially inwardend of the member 58 and is closed at its axially outward end.Preferably, the annular members 57 and 58 are identical so that they maybe made in the same mold.

The corresponding pairs of recesses 61, 62 are posi'- tioned inalignment with each other to receive the opposite ends of correspondingindividual coil springs 63. In addition to acting as a spring retainer,the .annular members 57 and 58 also act as end Iwashers for the springs.

As shown in FIG. l, the springs 63 are under compression and force therespective members 57 and 58 away from each other, with the outer end ofthe member 57 engaging the internal shoulder 55 on the housing end cap54 and the shoulder 51a on nut 51, while the outer end lof the member 58abuts against the end of the valve body 10 and the outer end of the endflange member -36 carried by the valve spool 30. In one practicalembodiment the adjacent ends iof the members 57 and 58 are spaced apartaxially from one another a distance of approximately .080 inch in theneutral or open-center position of the parts shown in FIG. l.

From FIG. 1 it will be apparent that the springs 63 positively bias thevalve spool 30 to the open center or neutral position. The biasing forcewhich these springs exert depends upon the number of springs used.Ordinarily, the number of springs required will be less than the numberof paired recesses y61, 62 in the members 57 and l58, so lthat some ofthese paired recesses will be empty. Preferably, the springs are more orless evenly distributed around the axis of the valve so as not to tendto tilt the members 57 and 58. In order to increase or decrease thespring bias, al1 that is necessary is to insert or remove one or moresprings '63 so as to get the biasing effect desired. This change may beeEected readily, simply by detaching the housing end cap 54 and thenmaking the desired change in the number of springs used. No basicredesign of the valve is required, nor is it necessary to change theoutside dimensions of the valve in order to make such changes.

Another advantage of the present arrangement is that the valve does notbecome totally defective in the event that one of the springs 63 shouldbreak. If this should happen, it 'would change the biasing force exertedbythe springs, but it would? not mean that the valve is no longer biasedto its neutral or open-centerposition. It would simply mean that thereaction or feel on the steering long-span sliding contact lofsubstantial extent at their re` respective bores 59 and 60 with theoutside of the sleeve member 50. For this reason there is no tendencyfor either of these members to become tilted so as to be like- 1y to'bejammed.

In theoperation of the valve,fwhenthe relative move" ment Ibetween valvebody 10 and rod 40 is such that rod 40 moves to the right in FIG. 1, thesleeve member 50, nut'51 and 'the "flange member`36 move to the right inunison with it and the valve spool 30. Nfut 51 moves the annular member57 to the right, while the other annular member 58 stays seated againstthe end wall of the valve body 10. Consequently, the bias springs 63ybecome more compressed.

When the actuating force on rod 40 is removed the bias springs 63 returnthe parts to the position shown in FIG. 1.

Conversely, when the relative movement between valve body 10 and rod 40is such that rod 40 moves to the left in FIG. 1, carrying with it thevalve sleeve 30, the sleeve member 50, nut '51 and the llange member 36also move to the left. This causes the annular member S8 to move to theleft while the other annular member 57 remains seated against theinternal annular shoulder 55 on the valve housing end capV 54.Consequently, the bias springs 63 become more compressed.

When the actuating force on rod -40l is relieved, these springs returnthe parts of the valve to the position shown in FIG. 1.

FIGURE 3 shows an alternative biasing arrangement which may be used inplace of the arrangement shown in FIG. 2. In this alternativearrangement a cylindrical spring retainer -body 70 is formed with aplurality of angularly spaced through openings 71 yfor receiving coilsprings 72. Each of these openings extends parallel to the axis of thevalve. The body 70 is formed with a central opening 73 for long-spansliding contact with the sleeve member 50. The outer periphery of body70 has a substantial radial clearance from the inside Wall 56a of thevalve housing end cap 54. Flat annular Washers 74 and 75A engage theopposite ends of the springs 72. These washers have central openings 74aand 75a, respectively, for slidably receiving the sleeve member 50. Theouter pen'pheries of these washers have substantial radial clearances`from the inside wall 56a of the housing end cap 54.

In the neutral, open center position the springs 72 bias the washer 74against the shoulders 55 and 51a and bias the washer 75 against the endsof valve body 110 and flange member '36.

When the relative movement between valve body and rod 40 is such thatrod 40 moves to the right in FIG. 3, the nut 51 moves washer 74 to theright while the other washer 75 stays seated against the end wall ofvalve body 10.

Conversely, when the relative movement between valve body 10 and rod 40is such that rod 40 moves to the left in FIG. 3, the llange member 36moves washer 75 to the left while the other washer 74 stays seatedagainst the internal shoulder 55 on the end cap 54 of the valve housing.

In this embodiment, as in the first-described embodiment, the biasingforce which the springs exert on the valve spool may be selectivelyvaried, simply by changing the number of springs. Ordinarily, the numberof springs 72 which are used will be less than the number of Aopenings71, so that some of these openings will be empty.

It is to be understood thatwhile there have been del scribed herein andillustrated in the accompanying' drawing two particular,presently-preferred embodiments ofv this invention, variousmodifications, omissions andre-- ,fnements which depart from thedisclosed embodiments l may be adopted without departing from thespiritfandscope ofthis invention.

What is claimed is:

1. In a valve,"valve housing meansdelining ow passages, a slidable valveuni'tin saidvalve. housing means, saidvalve housing means and saidslidablevalve unit being 'relatively movablewi-th respect to oneVanotherv inl opposite directions lfrom a neutral position of -saidslidable valve uni-t -insaidvalve housing meansto controlthellow of-fluid through said llow passages, said A valve housing means definingan annular space which is" disposed completely to one side axially ofsaid -flow passages and which extends circumferentially completelyaround said slidable valve unit, said valve housing means at theopposite axial ends of said annular space presenting a pair ofoppositely facing, radially disposed, annular walls, annular springreaction means in said `annular space, said last-mentioned meanscomprising a pair of annular members relatively slidable axially withrespect to said valve housing mean-s and with respect Ito said sliidablevalve unit, one of said annular members being mounted to remainstationary with respect to said slidable valve un-it and the other ofsaid annular members being mounted to remain stationary with respect tosaid valve housing means in one direction of the relative movementbetween said valve housing means and `Said slidable valve unit lfromsaid neutral position, said one annular member being mounted to remainstationary with respect to said valve housing means and said otherannular member being mounted to remain stationary with respect to saidslidable valve unit in the opposite direction of the relative movementbetween said valve housing means and said slidable valve -unit from saidneutral position, said annular springv reaction means also having aplurality, greater than two, of separate, axially extending springrecesses which are spaced apart in succession cincumferentially aboutsaid slidable valve unit, and individual springs removably received insaid recesses and under compression between said annular members andbiasing the latter against said walls to thereby bias said slidablevalve unit to said neutral position.

2r. The valve of claim 1 wherein said spring recesses are aligned,axially inwardly-facing recesses formed in said annular members.

3. The valve of claim 2 wherein each of said annular members has along-span sliding support of substantial axial extent in said annularspace.

4. The valve of claim 1 wherein said annular members are at washers, andwherein there is provided an annular spring retainer body between saidwashers which has through openings defining said spring recesses.

5. In a valve, a 'valve body having ilow passages therein, a slidablevalve unit in said valve body projecting axially beyond one end of saidbody, said valve unit being slidable in said Ivalve body in oppositedirections from a neutral position to control the flow of fluid throughsaid llow passages, a hollow end cap detachably secured to said valvebody at said one end thereof, said end cap receiving the projecting endof said slidable valve 4unit and providing an lannular space extendingcircumferentially completely around the latter, said one end of thevalve body presenting a radially disposed annular Wall which defines oneaxial end of said yannular space, said end cap presenting a radiallydisposed annular wall spaced axially from said one end of the valve bodyand dening the opposite axial end of said annular space, annular springreaction means in said annular space, said spring reaction meanscomprising a pair of annular members relatively slidable axially withrespect to said valve body and end cap and with respect to said slidablevalve unit, one of said annular members being `moun`ted to' remainstationary with respect to said slidable valve unit and the other ofsaid annular members being ber being mounted to remain stationary withrespect to t said val've body and said other vannular member beingmounted to remain stationary with respectl to said slidab-le valve unitin the opposite direction of sliding movement of said slidable valveunit from said neutral position, said annular spring reaction means alsohaving la n plurality, greater than two, of separate, axially extendingspririgrrecesses which are spaced 'apart in succession circumferentiallyaboutsaid slidable valve unit, and in- 1`5 dividual springs removablyreceived in said recesses and engaged, under compression between said'annular memf bers l'and biasing' the latter in opposite axialdirections against said lannular walls respectively tothereby bias saidslidable'valve unit to'said neutral position. s References Cited' in thele of this patent -UN ITED STATES PATENTS 1,605,399 Fornaca Nov. 2, 19261,753,0QA. Rode v Apr. 1, 1930 2,82A,3l4 Davis Feb. 25, 1958 2,879,748Banker Mar. 31, 1959 2,914,085 Banker Nov. Z4, 1959 2,997,064 Gerwig etal. Aug. 22, 1961 A FOREIGN PATENTS- 82,3;924 Great Britain Nov. 18,1959

1. IN A VALVE, VALVE HOUSING MEANS DEFINING FLOW PASSAGES, A SLIDABLEVALVE UNIT IN SAID VALVE HOUSING MEANS, SAID VALVE HOUSING MEANS ANDSAID SLIDABLE VALVE UNIT BEING RELATIVELY MOVABLE WITH RESPECT TO ONEANOTHER IN OPPOSITE DIRECTIONS FROM A NEUTRAL POSITION OF SAID SLIDABLEVALVE UNIT IN SAID VALVE HOUSING MEANS TO CONTROL THE FLOW OF FLUIDTHROUGH SAID FLOW PASSAGES, SAID VALVE HOUSING MEANS DEFINING AN ANNULARSPACE WHICH IS DISPOSED COMPLETELY TO ONE SIDE AXIALLY OF SAID FLOWPASSAGES AND WHICH EXTENDS CIRCUMFERENTIALLY COMPLETELY AROUND SAIDSLIDABLE VALVE UNIT, SAID VALVE HOUSING MEANS AT THE OPPOSITE AXIAL ENDSOF SAID ANNULAR SPACE PRESENTING A PAIR OF OPPOSITELY FACING, RADIALLYDISPOSED, ANNULAR WALLS, ANNULAR SPRING REACTION MEANS IN SAID ANNULARSPACE, SAID LAST-MENTIONED MEANS COMPRISING A PAIR OF ANNULAR MEMBERSRELATIVELY SLIDABLE AXIALLY WITH RESPECT TO SAID VALVE HOUSING MEANS ANDWITH RESPECT TO SAID SLIDABLE VALVE UNIT, ONE OF SAID ANNULAR MEMBERSBEING MOUNTED TO REMAIN STATIONARY WITH RESPECT TO SAID SLIDABLE VALVEUNIT AND THE OTHER OF SAID ANNULAR MEMBERS BEING MOUNTED TO REMAINSTATIONARY WITH RESPECT TO SAID VALVE HOUSING MEANS IN ONE DIRECTION OFTHE RELATIVE MOVEMENT BETWEEN SAID VALVE HOUSING MEANS AND SAID SLIDABLEVALVE UNIT FROM SAID NEUTRAL POSITION, SAID ONE ANNULAR MEMBER BEINGMOUNTED TO REMAIN STATIONARY WITH RESPECT TO SAID VALVE HOUSING MEANSAND SAID OTHER ANNULAR MEMBER BEING MOUNTED TO REMAIN STATIONARY WITHRESPECT TO SAID SLIDABLE VALVE UNIT IN THE OPPOSITE DIRECTION OF THERELATIVE MOVEMENT BETWEEN SAID VALVE HOUSING MEANS AND SAID SLIDABLEVALVE UNIT FROM SAID NEUTRAL POSITION, SAID ANNULAR SPRING REACTIONMEANS ALSO HAVING A PLURALITY, GREATER THAN TWO, OF SEPARATE, AXIALLYEXTENDING SPRING RECESSES WHICH ARE SPACED APART IN SUCCESSIONCIRCUMFERENTIALLY ABOUT SAID SLIDABLE VALVE UNIT, AND INDIVIDUAL SPRINGSREMOVABLY RECEIVED IN SAID RECESSES AND UNDER COMPRESSION BETWEEN SAIDANNULAR MEMBERS AND BIASING THE LATTER AGAINST SAID WALLS TO THEREBYBIAS SAID SLIDABLE VALVE UNIT TO SAID NEUTRAL POSITION.